Setting up data
Data from Human Mortality Database and Human Fertility Database was used to calculate birth rates. This was tidied to give Under-18 rates:
| 5 |
Denmark |
1990 |
2.94 |
26891.44 |
1.04 |
2.88 |
84.84 |
| 5 |
Denmark |
1991 |
2.65 |
27011.39 |
1.04 |
3.41 |
84.87 |
| 5 |
Denmark |
1992 |
3.08 |
29569.65 |
1.04 |
4.08 |
84.90 |
| 5 |
Denmark |
1993 |
2.90 |
27597.97 |
1.04 |
6.89 |
84.92 |
| 5 |
Denmark |
1994 |
2.71 |
29995.57 |
1.05 |
9.66 |
84.95 |
| 5 |
Denmark |
1995 |
2.19 |
35351.38 |
1.05 |
15.71 |
84.98 |
Abortion estimates were added to give Under-20 rates:
| 4 |
Denmark |
1990 |
26.51 |
9.20 |
26891.44 |
1.05 |
2.88 |
84.84 |
| 4 |
Denmark |
1991 |
25.33 |
9.00 |
27011.39 |
1.04 |
3.41 |
84.87 |
| 4 |
Denmark |
1992 |
25.43 |
9.70 |
29569.65 |
1.04 |
4.08 |
84.90 |
| 4 |
Denmark |
1993 |
24.81 |
9.14 |
27597.97 |
1.05 |
6.89 |
84.92 |
| 4 |
Denmark |
1994 |
24.07 |
9.21 |
29995.57 |
1.05 |
9.66 |
84.95 |
| 4 |
Denmark |
1995 |
23.08 |
8.72 |
35351.38 |
1.05 |
15.71 |
84.98 |
Removing non-fitting countries
Several countries were removed (detail added later).
Iterating through year combinations
For each comparison, I iterated through all combinations of years as special predictors to minimise MSPE (whilst prioritising fewest groupings). For example, for the under-18 basic model with years as special predictors:
it_u18_sp <- testSynthIterations(
yrs = 1990:1998,
pred = "rate",
data = synthData_u18[,1:4],
ccodes = u_18_ccodes,
n = 4,
predictors = NULL,
time.optimise = 1985:1998
) %>%
arrange(groups, mspe)
All countries, no additional predictors
Model 1: Under-18 birth rates
All Countries graph

England vs Synthetic Control
Over the period 1999 to 2013, England and Wales saw a difference of -3,744 births (to an average population of 995,340 women).

Weights and balance
Country weights
| Scotland |
0.672 |
| Portugal |
0.295 |
| United States of America |
0.016 |
| New Zealand |
0.012 |
| Iceland |
0.001 |
| Sweden |
0.001 |
| Switzerland |
0.000 |
| Germany |
0.000 |
| Denmark |
0.000 |
| Spain |
0.000 |
| Finland |
0.000 |
| France |
0.000 |
| Italy |
0.000 |
| Netherlands |
0.000 |
| Norway |
0.000 |
Predictor weights
| special.rate.1990.1993 |
0.01 |
| special.rate.1994 |
0.333 |
| special.rate.1995 |
0.295 |
| special.rate.1996.1998 |
0.362 |
Predictor balance between synthetic and treated units
| special.rate.1990.1993 |
16.214 |
16.275 |
10.415 |
| special.rate.1994 |
15.078 |
14.952 |
9.629 |
| special.rate.1995 |
15.285 |
15.561 |
9.660 |
| special.rate.1996.1998 |
16.836 |
16.728 |
9.257 |
Placebo testing by country and time
In placebo-country tests, England and Wales ranked 14 out of 16 countries by pre/post-MSPE ratio.

Model 2: Under-20 pregnancy rates
All Countries graph

England vs Synthetic Control
Over the period 1999 to 2013, England and Wales saw a difference of 152,471 pregnancies (to an average population of 1,668,190 women).

Weights and balance
Country weights
| Scotland |
0.639 |
| United States of America |
0.227 |
| Iceland |
0.134 |
| Switzerland |
0.000 |
| Germany |
0.000 |
| Denmark |
0.000 |
| Spain |
0.000 |
| Finland |
0.000 |
| France |
0.000 |
| Italy |
0.000 |
| Netherlands |
0.000 |
| Norway |
0.000 |
| Portugal |
0.000 |
| New Zealand |
0.000 |
| Sweden |
0.000 |
Predictor weights
| special.pRate.1990 |
0.152 |
| special.pRate.1991.1995 |
0.578 |
| special.pRate.1996.1998 |
0.271 |
Predictor balance between synthetic and treated units
| special.pRate.1990 |
68.000 |
65.337 |
35.661 |
| special.pRate.1991.1995 |
60.620 |
62.055 |
32.224 |
| special.pRate.1996.1998 |
63.633 |
61.259 |
30.895 |
Placebo testing by country and time
In placebo-country tests, England and Wales ranked 11 out of 16 countries by pre/post-MSPE ratio.

Filtered to remove Scotland, no additional predictors
Model 3: Under-18 birth rates
England vs Synthetic Control
Over the period 1999 to 2013, England and Wales saw a difference of -17,765 births (to an average population of 995,340 women).

Loss-V (For optimised period) = 0.616, MSPE (for whole pre-intervention observation period) = 0.616.
Weights and balance
Country weights
| Portugal |
0.807 |
| New Zealand |
0.193 |
| Switzerland |
0.000 |
| Germany |
0.000 |
| Denmark |
0.000 |
| Spain |
0.000 |
| Finland |
0.000 |
| France |
0.000 |
| Iceland |
0.000 |
| Italy |
0.000 |
| Netherlands |
0.000 |
| Norway |
0.000 |
| Sweden |
0.000 |
| United States of America |
0.000 |
Predictor weights
| special.rate.1990.1993 |
0.206 |
| special.rate.1994 |
0.156 |
| special.rate.1995 |
0.318 |
| special.rate.1996.1998 |
0.32 |
Predictor balance between synthetic and treated units
| special.rate.1990.1993 |
16.214 |
16.587 |
9.928 |
| special.rate.1994 |
15.078 |
15.963 |
9.210 |
| special.rate.1995 |
15.285 |
15.782 |
9.155 |
| special.rate.1996.1998 |
16.836 |
15.803 |
8.607 |
Placebo testing by country and time
In placebo-country tests, England and Wales ranked 14 out of 16 countries by pre/post-MSPE ratio.

Model 4: Under-20 pregnancy rates
England vs Synthetic Control
Over the period 1999 to 2013, England and Wales saw a difference of 250,707 pregnancies (to an average population of 1,668,190 women).

Loss-V (For optimised period) = 6.03, MSPE (for whole pre-intervention observation period) = 6.03.
Weights and balance
Country weights
| Iceland |
0.359 |
| United States of America |
0.353 |
| New Zealand |
0.288 |
| Switzerland |
0.000 |
| Germany |
0.000 |
| Denmark |
0.000 |
| Spain |
0.000 |
| Finland |
0.000 |
| France |
0.000 |
| Italy |
0.000 |
| Netherlands |
0.000 |
| Norway |
0.000 |
| Portugal |
0.000 |
| Sweden |
0.000 |
Predictor weights
| special.pRate.1990 |
0.309 |
| special.pRate.1991.1995 |
0.498 |
| special.pRate.1996.1998 |
0.193 |
Predictor balance between synthetic and treated units
| special.pRate.1990 |
68.000 |
67.005 |
34.180 |
| special.pRate.1991.1995 |
60.620 |
62.152 |
30.590 |
| special.pRate.1996.1998 |
63.633 |
60.236 |
28.987 |
Placebo testing by country and time
In placebo-country tests, England and Wales ranked 9 out of 15 countries by pre/post-MSPE ratio.

Adding all predictors
Model 5: Under-18 birth rates
England vs Synthetic Control

Loss-V (For optimised period) = 2.5, MSPE (for whole pre-intervention observation period) = 2.5.
Weights and balance
Country weights
| Italy |
0.374 |
| Iceland |
0.328 |
| United States of America |
0.298 |
| Switzerland |
0.000 |
| Germany |
0.000 |
| Denmark |
0.000 |
| Spain |
0.000 |
| Finland |
0.000 |
| France |
0.000 |
| Netherlands |
0.000 |
| Norway |
0.000 |
| Portugal |
0.000 |
| Sweden |
0.000 |
Predictor weights
| special.rate.1990.1993 |
0.028 |
| special.rate.1994 |
0.023 |
| special.rate.1995 |
0.034 |
| special.rate.1996.1998 |
0.15 |
| special.GDPperCap.1990.2003 |
0.014 |
| special.GDPperCap.2004 |
0.078 |
| special.GDPperCap.2005.2010 |
0.014 |
| special.GDPperCap.2011.2013 |
0.002 |
| special.edu_spend.1995.1998 |
0.003 |
| special.edu_spend.1999.2007 |
0 |
| special.edu_spend.2008.2013 |
0.13 |
| special.MobilePhones.1990.1992 |
0 |
| special.MobilePhones.1993.1995 |
0.022 |
| special.MobilePhones.1996.1997 |
0.011 |
| special.MobilePhones.1998.2013 |
0.126 |
| special.UrbanPop.1990 |
0.092 |
| special.UrbanPop.1991 |
0.088 |
| special.UrbanPop.1992 |
0.087 |
| special.UrbanPop.1993.2013 |
0.098 |
Predictor balance between synthetic and treated units
| special.rate.1990.1993 |
16.214 |
17.099 |
8.005 |
| special.rate.1994 |
15.078 |
16.268 |
7.329 |
| special.rate.1995 |
15.285 |
16.157 |
7.099 |
| special.rate.1996.1998 |
16.836 |
14.511 |
6.703 |
| special.GDPperCap.1990.2003 |
24800.333 |
26808.216 |
26870.008 |
| special.GDPperCap.2004 |
39983.985 |
39557.010 |
39108.220 |
| special.GDPperCap.2005.2010 |
43340.344 |
44960.799 |
47573.339 |
| special.GDPperCap.2011.2013 |
41975.732 |
43998.534 |
52420.115 |
| special.edu_spend.1995.1998 |
4.223 |
5.330 |
5.616 |
| special.edu_spend.1999.2007 |
5.296 |
5.885 |
5.627 |
| special.edu_spend.2008.2013 |
5.794 |
5.884 |
5.691 |
| special.MobilePhones.1990.1992 |
2.256 |
2.896 |
2.778 |
| special.MobilePhones.1993.1995 |
6.881 |
7.278 |
7.214 |
| special.MobilePhones.1996.1997 |
13.808 |
18.177 |
18.310 |
| special.MobilePhones.1998.2013 |
98.113 |
95.733 |
93.736 |
| special.UrbanPop.1990 |
78.140 |
77.151 |
74.238 |
| special.UrbanPop.1991 |
78.112 |
77.323 |
74.478 |
| special.UrbanPop.1992 |
78.172 |
77.514 |
74.734 |
| special.UrbanPop.1993.2013 |
79.690 |
79.327 |
77.582 |
Placebo testing by country
In placebo-country tests, England and Wales ranked 5 out of 14 countries by pre/post-MSPE ratio.

Model 6: Under-20 pregnancy rates
England vs Synthetic Control

Loss-V (For optimised period) = 17.2, MSPE (for whole pre-intervention observation period) = 17.2.
Weights and balance
Country weights
| United States of America |
0.522 |
| Iceland |
0.278 |
| Italy |
0.201 |
| Switzerland |
0.000 |
| Germany |
0.000 |
| Denmark |
0.000 |
| Spain |
0.000 |
| Finland |
0.000 |
| France |
0.000 |
| Netherlands |
0.000 |
| Norway |
0.000 |
| Portugal |
0.000 |
| Sweden |
0.000 |
Predictor weights
| special.pRate.1990 |
0.175 |
| special.pRate.1991.1995 |
0.156 |
| special.pRate.1996.1998 |
0.315 |
| special.MobilePhones.1990.1992 |
0 |
| special.MobilePhones.1993.1995 |
0.001 |
| special.MobilePhones.1996.1997 |
0.004 |
| special.MobilePhones.1998.2013 |
0.054 |
| special.edu_spend.1995.1998 |
0 |
| special.edu_spend.1999.2007 |
0 |
| special.edu_spend.2008.2013 |
0.001 |
| special.GDPperCap.1990.2003 |
0 |
| special.GDPperCap.2004 |
0.014 |
| special.GDPperCap.2005.2010 |
0 |
| special.GDPperCap.2011.2013 |
0.006 |
| special.UrbanPop.1990 |
0.11 |
| special.UrbanPop.1991 |
0.087 |
| special.UrbanPop.1992 |
0.071 |
| special.UrbanPop.1993.2013 |
0.004 |
Predictor balance between synthetic and treated units
| special.pRate.1990 |
68.000 |
68.849 |
32.961 |
| special.pRate.1991.1995 |
60.620 |
63.155 |
29.104 |
| special.pRate.1996.1998 |
63.633 |
57.510 |
27.083 |
| special.MobilePhones.1990.1992 |
2.256 |
3.182 |
2.778 |
| special.MobilePhones.1993.1995 |
6.881 |
8.184 |
7.214 |
| special.MobilePhones.1996.1997 |
13.808 |
18.494 |
18.310 |
| special.MobilePhones.1998.2013 |
98.113 |
85.702 |
93.736 |
| special.edu_spend.1995.1998 |
4.223 |
5.570 |
5.616 |
| special.edu_spend.1999.2007 |
5.296 |
6.133 |
5.627 |
| special.edu_spend.2008.2013 |
5.794 |
6.239 |
5.691 |
| special.GDPperCap.1990.2003 |
24800.333 |
28604.113 |
26870.008 |
| special.GDPperCap.2004 |
39983.985 |
41170.217 |
39108.220 |
| special.GDPperCap.2005.2010 |
43340.344 |
46569.676 |
47573.339 |
| special.GDPperCap.2011.2013 |
41975.732 |
46884.569 |
52420.115 |
| special.UrbanPop.1990 |
78.140 |
77.870 |
74.238 |
| special.UrbanPop.1991 |
78.112 |
78.125 |
74.478 |
| special.UrbanPop.1992 |
78.172 |
78.389 |
74.734 |
| special.UrbanPop.1993.2013 |
79.690 |
80.692 |
77.582 |
Placebo testing by country
In placebo-country tests, England and Wales ranked 8 out of 14 countries by pre/post-MSPE ratio.
